1. Field of the Invention
This invention relates to devices for measuring flow rates, and more specifically to a traveling wave flow meter having an undulating flexible membrane, wherein the velocity of propagation of a traveling wave associated with the flexible membrane is a function of volumetric flow.
2. Description of the Prior Art
A traveling wave flow meter having an undulating flexible membrane whose frequency is a function of volumetric flow is described in U.S. Pat. No. 4,358,954, entitled "Traveling Wave Flow Meter", issued Nov. 16, 1982 to Joannes de Jong. The flow meter includes a strip of flexible material having a length X which is forced to occupy a length of channel L, wherein (L-X). As a result, the flexible membrane buckles and assumes a wavelike shape inside the channel. When fluid is forced to flow through the channel, the flexible membrane undulates in a traveling wave type of displacement and the frequency of the traveling wave is a function of the volumetric flow rate of the fluid through the channel.
The response time of the above described traveling wave flow meter is relatively slow, since the response time is dictated by the frequency of the undulating flexible membrane. In interfacing the traveling wave flow meter with electronic processing devices, the relatively slow response time may prove to be particularly disadvantageous. Accordingly, there is a need for a traveling wave flow meter having a relatively fast response time.